This invention relates to novel esters of 6-(2-carboxy-2-phenylacetamido)penicillanic acid and of 6-[2-carboxy-2-(3-thienyl)acetamido]penicillanic acid which are of value as antibacterial agents. More particularly, said compounds are esters of 1,1-dioxopenicillanoyloxy-1-alkanols in which the hydroxy group is esterified with the 2-carboxy group of the 6-acyl group of said penicillanic acid compound. It also relates to intermediates useful for production of said esters.
British patent application No. 2,044,255, published Oct. 15, 1980 discloses 1,1-dioxopenicillanoyloxyalkyl- and 1,1-dioxopenicillanoyloxyaralkyl esters of 6-(2-carboxy-2-phenylacetamido)penicillanic acid and of 6-[2-carboxy-2-(3-thienyl)acetamido]penicillanic acid in which the 3-carboxy group of the penicillanic acid moiety is esterified. Belgian Pat. No. 883,299 describes certain 6'-acylaminopenicillanoyloxymethyl esters of penicillanic acid 1,1-dioxide, including the above-named esters; and the 6'-aminopenicillanoyloxymethyl esters of penicillanic 1,1-dioxide. The former esters are antibacterial agents and the latter are intermediates therefor.
Chloromethyl esters of a variety of penicillins, including alpha-carboxybenzylpenicillin, in which the 3-carboxy group is esterified, and the use thereof as intermediates for preparation of aminoacyloxy methyl penicillanates are described in U.S. Pat. No. 3,951,957, issued Apr. 20, 1976. British Pat. No. 1,303,491, published Jan. 17, 1973, discloses many 6'-acylaminopenicillanoyloxymethyl 6-acylaminopenicillanates and 6'-acylaminopenicillanoyloxymethyl 6-aminopenicillanates as antibacterial agents and chloromethyl 6-aminopenicillanate as an intermediate therefor.